I think having bumblebees would be neat though - our wild ones here love watching people, go about doing their business and enjoy living in my fence posts. They are like little teddy bears with wings lol.

Hey Beemaster, Are you sure you're not thinking of carpander bees? Bummble bees nest underground or in piles of grass. Carpander bees look like bummble bees but, have no hair on the surface of their abdomens. Just a heads up .

would it be possible to put the hive in the greenhouse with an outside entrance solely for the purpose wintering or is it possible to orient them where there is a window to get outside through the greenhouse so they are not exclusively pollinating the green house and get some benifit? It also occurs to me that a cheaply constructed hoop house put around a weak hive might get it through the wintermaybe with an escape where the weather is variable. Just trying to think outside the box. :)